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iOS Swift 2.0 Collections and Control Flow Control Flow With Conditional Statements Working with Switch Statements

Raphael Reiter
Raphael Reiter
6,820 Points
Posted by Raphael Reiter
Raphael Reiter
6,820 Points

working with switch statements challenge

hey guys, im stuck. anyone has the answer to this challenge? cheers R

2 Answers

Matthew Young
Matthew Young
5,133 Points
Matthew Young
Matthew Young
5,133 Points

I believe this is the correct answer:

The for statement is declaring the variables with the "world" dictionary as "key" for the Key and "value" as the Value associated with "key". The switch statement is then taking the current value for "key" and comparing it to the cases defined within the closure of the switch statement. If "key" matches any of the cases, then the respective code is executed.

For example, the first key that's used is "BEL". "BEL" matches the first case in the switch closure so the code "europeanCapitals.append(value)" is executed. The result of that code is the value of "value", which in this example is "Brussels", gets appended to the "europeanCapitals" array.

The default case in the switch statement is for anything that doesn't match up with the other specified cases (for example, "USA").

The for closure is then repeated for as many Keys as there are in the Dictionary (which is 8).

for (key,value) in world {
    switch key {
    case "BEL","LIE","BGR": europeanCapitals.append(value)
    case "VNM","IND": asianCapitals.append(value)
    default: otherCapitals.append(value)
    }
}
Mckinsley Apollon
Mckinsley Apollon
7,586 Points
Mckinsley Apollon
Mckinsley Apollon
7,586 Points

Put each key on seperate cases. Worked for me

var europeanCapitals: [String] = []
var asianCapitals: [String] = []
var otherCapitals: [String] = []

let world = [
  "BEL": "Brussels", 
  "LIE": "Vaduz", 
  "BGR": "Sofia", 
  "USA": "Washington D.C.", 
  "MEX": "Mexico City", 
  "BRA": "Brasilia", 
  "IND": "New Delhi", 
  "VNM": "Hanoi"]

for (key, value) in world {
    // Enter your code below
    switch key {
      case "LIE": europeanCapitals.append(value)
      case "BEL": europeanCapitals.append(value)
      case "BGR": europeanCapitals.append(value)
      case "VNM": asianCapitals.append(value)
      default: otherCapitals.append(value)
    }
    // End code
}